Configuring pin as input or output in Embedded C - Interactive Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to set pin 5 as an output.

Embedded C

DDRB |= (1 << [1]);

Drag options to blanks, or click blank then click option'

A3

B5

C7

D0

Attempts:

3 left

💡 Hint

Common Mistakes

Using the wrong pin number in the bit shift.

Forgetting to use the bitwise OR operator.

Setting bit 5 in DDRB configures pin 5 as an output.

2fill in blank

medium

Complete the code to configure pin 2 as an input.

Embedded C

DDRD &= ~(1 << [1]);

Drag options to blanks, or click blank then click option'

A1

B3

C4

D2

Attempts:

3 left

💡 Hint

Common Mistakes

Using bitwise OR instead of AND to clear the bit.

Shifting by the wrong pin number.

Clearing bit 2 in DDRD configures pin 2 as an input.

3fill in blank

hard

Fix the error in the code to set pin 7 as output.

Embedded C

DDRC [1] (1 << 7);

Drag options to blanks, or click blank then click option'

A|=

B&=

C^=

D=

Attempts:

3 left

💡 Hint

Common Mistakes

Using '=' which overwrites the entire register.

Using '&=' which clears bits instead of setting.

Use '|=' to set bit 7 without affecting other bits.

4fill in blank

hard

Fill both blanks to configure pin 4 as input and enable pull-up resistor.

Embedded C

DDRB [1] ~(1 << 4);
PORTB [2] (1 << 4);

Drag options to blanks, or click blank then click option'

A&=

B|=

C^=

D=

Attempts:

3 left

💡 Hint

Common Mistakes

Using '=' instead of '&=' or '|='.

Not enabling the pull-up resistor after setting input.

Use '&=' with negated bit mask to set pin as input, and '|=' to enable pull-up resistor.

5fill in blank

hard

Fill all three blanks to configure pin 3 as output, set it high, and clear pin 6 as input.

Embedded C

DDRD [1] (1 << 3);
PORTD [2] (1 << 3);
DDRD [3] ~(1 << 6);

Drag options to blanks, or click blank then click option'

A|=

C&=

D^=

Attempts:

3 left

💡 Hint

Common Mistakes

Using '^=' which toggles bits instead of setting or clearing.

Mixing up PORTD and DDRD registers.

Use '|=' to set pin 3 as output and set it high, and '&=' with negation to clear pin 6 as input.